It looks like the Lollipop Smart Lock can unlock your phone when it's in proximity to your PC, whereas nearlock will unlock your PC when it's in proximity to your phone.
This feature is only available within Android 5.0, however, and the pool of devices running Lollipop at the moment is pretty much limited to the Nexus line.
Although it is only available on Lollipop, I find it pretty neat that these features have native support. The caveat about setting a trusted place to unlock is straight out of Tomorrow Never Dies[0]:
"Be aware that location signals can be replicated or manipulated — someone with access to specialised equipment could unlock your device."
https://support.google.com/nexus/answer/6093922?hl=en-CA